Magnetostatic wave propagation characteristics at low temperatures

Low temperature characteristics are studied for the linear and nonlinear magnetostatic wave (MSW) propagation in yttrium iron garnet (YIG) films theoretically and experimentally. It is confirmed that the saturation magnetization is the only factor which governs the propagation characteristics at low temperatures. Moreover, the ferromagnetic resonance (FMR) linewidth /spl Delta/H of a YIG film is measured from the propagation loss and delay of MSW, and it is found that the /spl Delta/H becomes larger at low temperatures.